GHK-Cu vs Melanotan I

GHK-Cu

Human evidence is mostly small cosmetic studies of topical formulations at roughly 0.05-2% concentration for skin appearance and hair. Systemic injectable use is supported by animal wound-healing data only, and the 1-2 mg daily figures come from community protocols rather than controlled trials. Cycle it rather than running it continuously because of copper load.

Melanotan I (Afamelanotide)

DO NOT CONFLATE THIS WITH MELANOTAN II — that is the single most common error made about this compound, and the two behave differently enough that the mistake matters. Melanotan I is the LINEAR alpha-MSH analogue [Nle4-D-Phe7]-alpha-MSH (afamelanotide): a 13-amino-acid straight-chain peptide that is essentially alpha-MSH with two residues swapped for stability, and it is relatively SELECTIVE FOR MC1R, the melanocyte receptor. Melanotan II is a smaller CYCLIC seven-residue peptide that hits MC1R, MC3R, MC4R and MC5R non-selectively. The MC3R/MC4R activity is where Melanotan II gets its spontaneous erections and priapism reports, its heavy nausea and vomiting, its yawning/stretching reaction and its appetite suppression. MELANOTAN I DOES NOT SHARE THAT PROFILE: it is not an erectogenic drug (that pharmacology is what PT-141/bremelanotide was developed from, and bremelanotide is a Melanotan II derivative, not a Melanotan I derivative), and its nausea and appetite effects are much weaker. What it does share is melanogenesis, and therefore the mole and melanoma-surveillance concern. THE APPROVAL STATUS IS ALSO DIFFERENT, AND THIS IS THE OTHER HALF OF THE CONFUSION. Afamelanotide IS an approved medicine: as SCENESSE it holds EMA approval (2014) and FDA approval (2019) for erythropoietic protoporphyria (EPP), a rare inherited photosensitivity disorder, where it increases eumelanin and raises the time patients can tolerate light exposure. Melanotan II is approved nowhere. That approval does NOT transfer to cosmetic use. The approved product is a 16 mg controlled-release SUBCUTANEOUS IMPLANT inserted by a trained clinician above the hip every two months, in a monitored EPP program that includes regular skin surveillance. It is not a self-injected lyophilized vial and it is not a nasal spray. The vials and sprays sold as "Melanotan 1" are unlicensed research-chemical product of unverified purity, with no approved label to anchor dosing to. The 250-1000 mcg daily figures here are grey-market convention only: Melanotan I is generally used at higher milligram totals than Melanotan II because it is less potent per microgram at MC1R uptake in practice, typically a daily loading phase until the target pigmentation is reached, then a much less frequent maintenance dose. Published pharmacokinetic figures for the free peptide are inconsistent and the implant PK is dominated by the release rate rather than the peptide, so no half-life is listed. Anyone using it should have a dermatologist skin check before starting and be monitored during and after, and it does not replace sun protection.